How and why you should do a weight check.
Whether you have just finished your Open Water course or you are getting reading for your PADI Divemaster course, knowing how to do a proper weight check is a skill you will use very often!
When we dive, we want to dive perfectly weighted, not dragging around too much weight or not having enough.
When diving underweighted, you might run into several problems:
– you may have difficulties descending
– you might be positively buoyant during the dive so you will need to dive in a head down position and keep kicking to stay down, which will result in using more energy and air
-the more air we use the air the lighter our tanks will become, so you will find it harder and harder for us to stay down
– you could float up uncontrollably to the surface
On the contrary, when diving with too much weight the following could happen:
– you could descent too fast and run into ear problems
– to get neutral underwater you would need to add air to your BCD. Similarly, at the surface, you might need to fully fill your BCD to stay afloat.
-underwater, the more our BCD is inflated, the more drag we create swimming through the water, which would make us use more energy and air
-the heavier we are we’d also use more energy and air to propel ourselves in the water.
These are a few of the reasons why good weighting is so important when we are diving!
To do a proper weight check:
– You want to do it with air in the tank around 50 bar (tank pressure at the end of a dive) and not when the tank is full. We want the perfect weighting at the end of the dive so we can do stops safely and comfortably.
– You can start by using about half of the weight you are normally carrying.
– With the regulator in, breathe in, hold that breath, then deflate the BCD completely.
– You should sink until the water level is somewhere around your mask/top of the head area.
– Breathe out completely emptying the lungs and see if you can slowly sink.
If you are not going down, add 1 kg and do the check again.
If you sink fast, then you are wearing too much weight, remove one and try again.
If you can go down nice and slow without having to hold the lungs empty for too long, then you’re perfectly weighted.
If you do the weight check in a freshwater pool then you will need to add somewhere between 1 and 3 kilos when going diving in the ocean as the salt water is denser.
When you have found your perfect weighting, this is what you will need with the configuration you are using to do the weight check.
So if you are to wear a different BCD, or different wetsuit (shortie or long, or different thickness), or maybe you have lost or gained some weight, then you will need to do a weight check again.
Perfect weighting takes practice and a bit of effort….but it is worth it!
Now you understand the basic principals of how to dive perfectly weighted.